This invention relates generally to aircraft engine power systems and, more particularly, to methods and apparatus for providing energy to and storing energy within or proximate to electrically driven flight control actuators.
Some known aircrafts use electrically driven flight control actuators. Although electrically driven actuators are more complex and less user-friendly than hydraulically or pneumatically driven actuators, electrically driven flight control actuators generally are lighter in weight, require less maintenance, and are more reliable than hydraulically or pneumatically driven flight control actuators. Known electrical power systems, however, channel regenerative transient energy back into the electrical power system, which increases a voltage of a primary power distribution bus. A high voltage of the primary power distribution bus may cause the bus voltage to be out of MIL-STD-704 specification, damage electric devices on the bus, or generate excessive heat on the aircraft, each of which may jeopardize a flight mission.
To facilitate storing transient energy, some known aircrafts use either a centralized battery based or battery/ultra-capacitor hybrid based energy storage to facilitate absorbing excessive energy returned from flight control actuators and releasing energy back to the actuators whey they require it. Using a centralized energy storage, however, may induce reliability issues to the electrical power system. For example, some known batteries have sensitive operating temperatures that, without a constant precise temperature control, may result in fires. For another example, some known batteries have sensitive battery lives that are prone to a rate and a depth of charge and discharge, especially when used in systems that require a high charging rate and an irregular pattern of charge and discharge cycles. Therefore, there is a need to provide a more reliable electrical power system that facilitates storing excessive energy returned from actuators.